[Remote clusters] Migrate to new ES client

x-pack/plugins/remote_clusters/common/lib/cluster_serialization.ts

@@ -8,13 +8,17 @@
 import { PROXY_MODE } from '../constants';
 
 // Values returned from ES GET /_remote/info
+/**
+ * TODO: This interface needs to be updated with values from {@link RemoteInfo} provided
+ * by the @elastic/elasticsearch client
+ */
 export interface ClusterInfoEs {
   seeds?: string[];
   mode?: 'proxy' | 'sniff';
   connected?: boolean;
   num_nodes_connected?: number;
-  max_connections_per_cluster?: number;
-  initial_connect_timeout?: string;
+  max_connections_per_cluster?: string | number;
+  initial_connect_timeout: string | number;
   skip_unavailable?: boolean;
   transport?: {
     ping_schedule?: string;
@@ -39,8 +43,8 @@ export interface Cluster {
   transportPingSchedule?: string;
   transportCompress?: boolean;
   connectedNodesCount?: number;
-  maxConnectionsPerCluster?: number;
-  initialConnectTimeout?: string;
+  maxConnectionsPerCluster?: string | number;
+  initialConnectTimeout?: string | number;
   connectedSocketsCount?: number;
   hasDeprecatedProxySetting?: boolean;
 }

x-pack/plugins/remote_clusters/server/lib/does_cluster_exist.ts

@@ -5,9 +5,14 @@
  * 2.0.
  */
 
-export async function doesClusterExist(callAsCurrentUser: any, clusterName: string): Promise<any> {
+import { IScopedClusterClient } from 'src/core/server';
+
+export async function doesClusterExist(
+  clusterClient: IScopedClusterClient,
+  clusterName: string
+): Promise<boolean> {
   try {
-    const clusterInfoByName = await callAsCurrentUser('cluster.remoteInfo');
+    const { body: clusterInfoByName } = await clusterClient.asCurrentUser.cluster.remoteInfo();
     return Boolean(clusterInfoByName && clusterInfoByName[clusterName]);
   } catch (err) {
     throw new Error('Unable to check if cluster already exists.');

x-pack/plugins/remote_clusters/server/plugin.ts

@@ -19,6 +19,8 @@ import {
   registerDeleteRoute,
 } from './routes/api';
 
+import { handleEsError } from './shared_imports';
+
 export interface RemoteClustersPluginSetup {
   isUiEnabled: boolean;
 }
@@ -44,6 +46,9 @@ export class RemoteClustersServerPlugin
       config: {
         isCloudEnabled: Boolean(cloud?.isCloudEnabled),
       },
+      lib: {
+        handleEsError,
+      },
     };
 
     features.registerElasticsearchFeature({